The Aj^2^lc. 



55 



scales interspersed with brown or blackened mature scales. 

 The larva are produced in successive generations from 

 spring until autumn frost, and multiply with extreme ra- 

 pidity. The San Jose scale is chiefly disseuiinateJ by nur- 

 sery stock. (24) 



Fig. 15. San Jose scale. A, natural size; b, enlarged. (After Howard, U. S. 

 Department of Agriculture.) 



Preventive measures. Infested nursery stock is best freed 

 from the San Jose scale by fumigating it in close rooms, 



